Hi hgks,
1 Yes, you can set time step interval arbitrarity
2 Yes, you can change directly the value of TREF or NTSPTC in the source code card images 7 and 8 in efdc.inp file. Or change in the “Simulation Timing Options” form
3 yes it is, it is not fixed to 86400(s), you can reduce it to whatever you want for example Duration of Reference Period =1=3600s
4 Can you upload your model here, I will take a look at it for you because it depends on the number of layers, the orthogonality of the grid…
5 Safety factor = 0: Constant time step is used. 0 < safety factor < 1: Dynamic time step. This factor is used a factor of the minimum time step then the dynamic time step will increase based on a ratio
Thank you,
Hoa